Perfect explanation by Manhattan folks:Question Type:
FlawArgument Core:
Conc - Pineal gland produces less melatonin as it ages
(why?)
P1 - Large study of 65-81 insomniacs showed that more melatonin helped
P2 - Melatonin is produced by the pineal gland
Okay, where did this conclusion come from? Where did we talk about how much melatonin the pineal gland produces?
How did the author get from the results of the study to this claim?
He must be assuming that "since giving insomniacs melatonin HELPED their insomnia, their insomnia must have been caused by insufficient melatonin."
Does that have to be true?
If I give a sad person $1000 and make them happier, does that mean their sadness was caused by not having enough money?
Of course not! Maybe they were say because their favorite NBA team just got eliminated from the playoffs but a sudden gift of $1000 is enough to distract them and perk them up.
So we could say that a flaw the author makes is "assuming that something that TREATS a certain problem was CAUSING the problem in the first place".
Another way to approach Flaw (and other Assumption Family questions) is simply to debate the conclusion.
The author claims the pineal gland produces less melatonin as it ages.
So we have to argue that the pineal gland produces the same (or more) as it ages.
AUTHOR: oh yeah? well then how come insomniacs got better when we gave them more melatonin? doesn't that suggest that they didn't have enough to begin with?
US: Maybe. But if Tylenol helps you get rid of your headache, does that mean your headache was caused by too little Tylenol in your bloodstream? We don't know the insomnia is caused by too little melatonin. But let's assume for a second that the problem IS caused by too little melatonin -- do we know that the pineal gland produces less as it ages? Did these people have insomnia when they were young? Maybe they've ALWAYS had too little melatonin. They might just have bad pineal glands, and this study has nothing to do with the effects of aging.
Let's check out answers:
(A) This sounds kinda tempting. It has causal wording. What "effect of an action" was there? The action of ingesting melatonin had the effect of helping insomnia. Did the author illicitly conclude that we had people ingest melatonin with the INTENT of helping their insomnia?
This answer deals with whether or not the experimenters intended to help insomnia by giving melatonin. Who cares?
We're debating whether or not the pineal gland produces less melatonin as it ages. Eliminate.
(B) This would tempt people because the conclusion mentions the manufacturers of melatonin supplements. But to RELY on their opinion means that their opinion was THE premise.
That's not at all accurate. The premise was the large study. We don't know who conducted the study. And the results of the study are not opinions. The author's argument relies only on the results of the study and knowledge that the pineal gland produces melatonin and relates to the sleep cycle. Eliminate.
(C) This old classic flaw? Next thing you know they'll offer me the ol' Circular Reasoning. Two Different Meanings and Circular Reasoning pop up in answer choices all the time and are almost always wrong. Did we identify a term that was used in two different ways? Nope. Eliminate.
(D) Causal language again ... did we have an effect of a phenomenon? Yes, the phenomenon of "taking melatonin" had the effect of "helping insomnia". Did the author get those backwards? Did "helping insomnia" really have the effect of "taking melatonin"?
That's crazy talk! I don't even know what that means. (D) is code for "reverse causality". That comes into play with correlation -> causality arguments.
Our causal issue here was with the reasoning of, "Since more X helps the problem, too little X must be causing the problem."
(E) Unrepresentative sample? Hmmm. Didn't think that was the problem. It IS a "large study". But wait --- it's a study of 65-81 year olds and the conclusion is about the pineal gland "as it ages".
Maybe we could object that this study doesn't help us analyze the pineal gland "as it ages" since it only looks at "aged people".
That's a bit weird, but it's kinda like the objection we had when we said "What if these people have ALWAYS had insomnia? How does this study show us that nowadays they have less melatonin in their system than previously?"
In order to draw a stronger conclusion about the pineal gland "as it ages", we would want to do a study that looks at insomniacs of all age groups.
If melatonin was only helping the older people, THAT would suggest that as you get older you need some more melatonin.
If melatonin was helping ALL age groups, then we wouldn't draw any conclusion about the pineal gland producing less M as it ages. We would probably just think "melatonin is an effective treatment for insomnia, and it looks like MAYBE insomnia is caused in part by having too little melatonin."
This is a tricky correct answer. Note that what will screw up most of us on this problem is that we are very likely to see the initial problem with this logic: "just because more X makes the problem go away doesn't mean that too little X was causing the problem in the first place".
We might call this the Primary Flaw. However, if you pretend for a second that we DO know that too little melatonin causes the problem, you STILL can find a Secondary Flaw, which is "how do we know the problem gets worse with age?"
This is typical of really hard Flaw problems -- the correct answer doesn't reward the Primary Flaw most of us initially notice ... you have to go along with some of the author's sketchy moves to get to ADDITIONAL problems with his thinking.